Electrical switch device



1955 A. H. MORGAN ETAL 3, 03

ELECTRICAL SWITCH DEVICE Filed NOV. 14, 1962 F76] H I I:

x Il 34: L 1 lf l mT 26 v 12 m a 23 V jg /0 2/0 35 United States Patent3,226,508 ELECTRICAL SWITCH DEVICE A. Henry Morgan, Norwalk, Walter B.Uhl, Fair'field, and Henry R. Angel, Trumbull, Conn., assignors toElectronic Controls, Inc., Stamford, Conn, a corporation of MarylandFiled Nov. 14, 1962, Ser. No. 237,625 19 Claims. (Cl. 200104) Thisapplication is a continuation-in-part of our c0- pending applicationSerial No. 146,499, filed October 20, 1961, now abandoned.

This invention relates to the field of switches and relays. Moreparticularly it relates to an improved multicontact switch and/or relayand methods of construction thereof.

The term switch includes both those devices which are locally operatedand commonly referred to as switches and those devices which areremotely operated and commonly referred to as relays.

In many application of switches it is necessary that each separatecontrol be able to handle many separate circuits and that related groupsof circuits be able to be controlled simultaneously. In much equipment acomplex of circuits is used to provide for the various functions to beperformed. Some of these circuits are directly controlled by othercircuits or by the happening of some mechanical event within theequipment such as the dwell of cam follower or the like; others must becontrollable by human selection. If these circuits were each to becontrolled by a separate switch or relay the number of elements requiredwould often be so great that the cost and the space required formounting would be prohibitive. To avoid this, and also to insure thatcircuits which must be affected simultaneously are so affected, a singleswitch or relay should be capable of controlling a great number of suchcircuits.

So great is the number of circuits to be controlled that the need forswitches capable of handling a large number of circuits, and notrequiring too much space, has still not been satisfactorily solved.Commercially available switches, whether manually controlled or of therelay type are either excessively large, difficult to operate,unreliable, or otherwise unsatisfactory.

Accordingly, it is an object of this invention to provide an improvedmulticontact switch and/or relay.

It is a further object of this invention to provide a multicontactswitch and/ or relay having a greater number of contact elements in asmaller space than previously possible.

The invention in its more comprehensive aspects provides a very simpleand dependable multiple-switch or gang-switch unit and in some of itsmore detailed aspects provides elements of a novel nature which alone orin mutual association contribute to the simplicity and dependability ofdevice.

With the increasing complexity of electrical circuits and controls ithas become very important and urgent that there be provided a multipleswitch unit which will operate with complete certainty in each and allcomponents over a very long period of service and under most exactingconditions. The present invention provides such a unit and in a formwihch is extremely simple to manufacture and assemble; which can beassembled with the simplest of tools, a screwdriver being the only toolrequired in most cases; which from a few standard components can readilybe assembled in a great range in the number of unit switches or unitgroups of switches in subassembly modules or in a single ultimateassembly device; which provides easy visual inspection of any in-;

dividual switch unit in the assembly; and which requires little increasein power needed for operation even if the number of units is greatlyincreased.

In its simplest aspect the invention provides a blade or leaf-typeswitch having improved mounting means for the anchorage end of themovable or shiftable blade element and similarly, when needed, for therelatively fixed blade elements. It also provides improved operatingmeans for the movable end of the shiftable blade element, this meansbeing particularly useful when parallel-paired, oppositely-paired andtier-paired switch units are operated.

The objects, features of novelty and advantages of the invention willbetter be understood from a consideration of some illustrativeembodiments, reference being made to the accompanying drawings, inwhich:

FIG. 1 is a section through the center of a symmetric embodiment of thisinvention;

FIG. 2 is an exploded view of a portion of the contact assembly shown inFIG. 1;

FIG. 3 is a section along line 33 of FIG. 1;

FIG. 4 is a section along line 44 of FIG. 1;

FIG. 5 is a side elevation of another embodiment of a multiple-switchdevice or assembly embodying the invention;

FIG. 6 is an end view of the assembly shown in FIG. 5;

FIG. 7 is an enlarged vertical section taken on the line 7-7 of FIG. 10;

FIG. 8 is a transverse vertical section taken on the line 8-8 of FIG. 7;

FIG. 9 is a transverse vertical section taken on the line 99 of FIG. 7;

FIG. 10 is a horizontal section taken on the line 1010 of FIG. 7;

FIG. 11 is an exploded perspective view of parts of a blade anchorageassembly;

FIG. 12 is a perspective view of a blade cage frame unlt;

FIG. 13 is a partial vertical section of a modified form; and

FIG. 14 is a partial vertical section of the form shown in FIG. 13 butat a different location.

Referring now to FIG. 1, a pair of movable contact arms or blades 10 areshown, though many more may be provided (cf. FIG. 3). One end of eacharm 10 is held by a post or sleeve 11 in a manner more clearly shown inFIG. 2. The other end of arm 10 lies in a slot 12 formed in a member 13.Member 13 is disposed transversely, specifically at right angles, toarms 10. Arms 10 have a contact portion 14 thereon. In the rest positionof the switch, portion 14 may be in contact with a contact point 15 on ablade or arm member 16 and, as will be seen, when the switch isactuated, portion 14 is moved into contact with a contact point 17 on ablade or arm member 18. Either or both of members 16 or 18 may beconnected to circuits to be controlled and are separated from each otherand arm 10 by insulating spacers 20a and 20b. As will be seen from FIG.2, spacers 20a and 20b not only insulate arms 10 and members 16 and 18from each other, but also function to secure them in place.

Slotted member 13 has a hole formed through it, in its center, throughwhich shaft or plunger 21 passes. A collar 21a on shaft 21 forces member13 down when upper plunger 22 forces shaft 21 down.

Shaft 21 may be directly controlled by manually operated upper plunger22 or, as in the embodiment shown, shaft 21 can be controlled by plunger22 through intermediate members indicated within bracket 26. Plunger 22is normally maintained in an elevated position by spring 23 and is movedagainst the force of that spring by the manual operation of plunger 22.Member 13 is restored by a spring indicated at 36 in FIG. 4.

An electromagnet, indicated at 24, may be provided, which can beenergized through a circuit completed by one of contact arms 10, toretain shaft 21 in a depressed position after it had been depressed bythe manual actuation of plunger 22, or which permit-s the unit to beused as a relay, the electromagnet itself actuating shaft 21. If sucharrangement is included, then of course, some methd of breaking theholding circuit energizing electromagnet 24 must be provided.

Also, if desired, provision may be made to indicate when the switch orrelay is made, i.e., when contact portions 14 have moved from points 15to points 17. As shown, this may be a lamp 25 mounted beneath plunger 22which plunger would have a translucent or transparent top portion. Lamp25 may be connected through an appropriate circuit either through thesame contact arm as electromagnet 24 or through a contact portion onanother of arms 10.

, In operation plunger 22 may be manually depressed against the pressureof spring 23. Plunger 22 in turn depresses shaft 21 through intermediatemembers and with it slotted member 13. When member 13 moves down itpivots arm 10 about its fixed point at sleeve 11, moving contact portion14 from contact point 15 to contact point 17. In this embodiment thismight complete a circuit energizing electromagnet 24 and lamp 25. Such acircuit would be conventional initself and illustration is not deemednecessary.

It will now be understood that no matter how many arms 10 are used, eachis directly and positively moved through the motion imparted to slottedmember 13. Location of contact portions 14 near slotted bar 13 increasesthe positive nature of this transfer of force.

Referring now to FIG. 2, a particular embodiment of the contact assemblyportion of the switch and/ or relay is shown. A blade member 30 has apair of notches 31 formed therein. These notches are shaped so thatopposite notches on adjacent arms define an aperture substantially theshape of sleevesll. In the illustnated embodiment, sleeves 11 arecylindrical and each notch 31 preferably is defined by an arc havingsubstantially the same radius of curvature as posts 11 and a length lessthan half the circumference of posts 11, thereby insuring that adjacentones of member 30 do not touch when positioned about sleeves 11.

Member 32, a lead connection blade, illustrates one way of providing.external connections from the switch assembly. Member 32 is alsoprovided with notches 31 in a manner identical to those of member 30 andthese two members, 30 and 32, are placed one on top of the other,between spacer bars'20a and b, positioned adjacent to apertures 33 sothat sleeves 11, when inserted through the apertures, will cooperatewith the notches to hold the members securely in position. Members 30and 32, together, may be considered to comprise arm 10, FIG. 1, ormember 30 alone could be that arm. Similarly, members 30 and 32,together, could be members 16 or 18 as well, since all of these areessentially the same in the portion illustrated in FIG. 2

It will be appreciated that only a portion of the contact assembly isillustrated in FIG. 2. If members 30 and 32 are considered to constitutearm 10 sandwiched between spacers 20a and 20b, then a pair of members 16and 18 have been omitted to avoid obscuring pertinent details of theconstruction. It should be appreciated that, as a result of theprovision of notches 31 which cooperate with sleeves 11, and spacers 20aand 20b, a rigid mounting is obtained without need for conventionalmethods of fastening, such as screws through the various members.

Top piece 34 cooperates with spacer 20a to hold member 16 in position,and bottom piece 35 similarly cooperates with spacer 20b to hold member18 in position. It should be understood that arm 10 or members 16 and 18could be constructed of one piece instead of the two shown, through theembodiment illustrated in FIG. 2

permits a choice of external connections to be offered. The entirecontact assembly may be held together by several fasteners which can beinserted through sleeves 11 and passing through appropriate apertures inswitch housing (FIG. 1) and which is indicated at 27 and 28 of FIG. 1.

The contact assembly illustrated in FIGS. 2, 3 and 4, may, in turn, bestacked simply by extending shaft 21 any desired length so as toprotrude through slotted member 13 and by providing an aperture inbottom piece so that shaft 21 can cooperate with other slotted members.

FIG. 3 shows more clearly the appearance of the contact assembly withthe topmost members 16 arranged side by side, and in the embodimentillustrated each contact assembly has twelve sets of contacts.

FIG. 4 illustrates a detail of the assembly of the switch or relay; thereturn spring which is indicated at 36 and which can be of anyconfiguration such that it opposes the downward travel of slotted member13 and shaft 21 and restores member 13 to its rest positions when theoperating force, e.g., depression of plunger 22 is removed.

When used as a relay, of course, the plunger portion of the assemblyshown in FIG. 1 could be eliminated and the unit would be operatedsolely by the electromagnet indicated at 24.

FIG. 5 shows a multiple-switch device or assembly 40 which comprises astack of substantially identical multipleswitch units, modules or wafers41 and a single manual operator or pushbutton 42, the units beingsecured together by a top plate 43 and a plurality of screws 44. Thelength of the screws is selected according to the number of tier, moduleor wafer units 41 which are assembled in the stacked composite unit orcomplete switch assembly device.

It has been found to be extremely helpful for inspection to form allpanels of a non-breakable transparent insulating material, such forexample as Lucite, Plexiglas, Lexan or the like, but no attempt has beenmade to show the material as being transparent because of the confusionwhich would be caused by showing in simple views all parts which couldbe seen. Lexan, a polycarbonate plastic, is at present preferred becauseof its high temperature resistance, dimensional stability, moistureresistance and other characteristics which are favorable for thepreferred use. Obviously, many other plastics are suitable for theapplication.

Each unit, module or wafer 41 comprises a housing which includes abottom wall 47, a top wall 48, side Walls 49 which may be interfitted bytongue and groove in the top and bottom walls so as to be removable byend sliding movement, and end walls 50 which, as shown in FIG. 11,comprise transverse spacer bars 51 and vertical spacers 52 which may bemade integrally with the transverse bars if desired. The verticalspacers 52 are mated with recesses 53 which provide variable spacing forclamping a plurality of switch blades or plates 54 of the flexible leaftype. The blades are provided on the sides with arcuate recesses ornotches 55 which embrace the sides of the vertical spacers 52 wherebythe blades are held firmly in position between the two transverse spacerbars 51. The spacer bars constitute anchorage means for the outer endsof the switch blades, the lower one being referred to as the base memberand the upper one as the clamp member. All housing parts are ofinsulating material, preferably a clear plastic, as stated.

At least some of the vertical spacers 52 are provided with apertures 56;and the transverse spacer bars 51,v and the top and bottom walls of thehousing are provided with aligned corresponding apertures for the screws44' which hold the assembled wafer units together and to the top plate43. Preferably each wafer unit has its. parts secured together to form aself-contained independent unit before it is secured in an assembly withother parts as here shown by tubular rivets 45.

As shown, there are three superposed rows of switch blades 54 anchoredin each end of each wafer or stack unit housing, all secured in the endwall anchorages in the same way but some having different functions fromothers. The upper row 54a and the lower row 540 of switch blades aresubstantially fixed, although all the switch blades here are springy orresilient and have some movement in operation; and the blades of themiddle row 54b are shiftable to move to cooperative positions relativeto the upper and lower rows. All switch blades are provided withcontacts 57 and it will be understood that the outer ends of the bladeswhich are exposed beyond the end wall of the housing have suitableelectrical conductor leads secured to them. As here shown, the outer endportions 54d are made as separate parts with notches like the main partof the blade. There are a number of advantages in making the switch andterminal blade elements of separate parts. One, which has already beenmentioned, is that it provides a choice of types of ter-- minalconnections at the outside.

while leaving the terminal portions soft. If desired, the outer terminalportions and the inner switch portions can be soldered or weldedtogether.

The switch blades of the middle row 54b have inner end extensions 58 bywhich the blades are actuated along lines transverse to the plane of theblades.

Means are provided for limiting or confining the movements of the switchblades to assure that all contacts of the row on one side of the movableblades are separated before. the contacts of the row on the other sideare brought together. The means here shown comprises transverse stopbars 60 located near the contacts, here outwardly or outboard of them.Here the bars comprise parts of a unitary cage grid 61 having apertures62 providing limited movement of the blades. The cage grid 61 is held atits upper and lower ends in grooves 63 formed in the bottom and topwalls 47, .8 respectively of the housing.

Means are provided for operating the movable or shiftable middle rowswitch blades by action on their end extensions 58, the means here showncomprising a transverse operating bar 65 which moves transversely to theplanes of the switch blades and is provided with elements whichoperatively engage the ends of the blades without binding during travel.The bar is here shown as being provided on each side with a slot orgroove 66 which receives the ends of all the shiftable blade ends on aside with such allowable end and side movement as may be necessary toavoid binding. The grooves are slightly over-depth and flared at top andbottom for such movement accommodation.

Means are provided for actuating each operating bar 65 for each housingmodule or wafer unit in a controlled manner, as by guide and preferablyanti-tilt arrangements, to assure that all switches of a bank or row areoperated at each actuation. As here shown an operating push rod orplunger 70 is rigidly connected to the bars 65 of all wafer units andthe plunger is guided, as by a sleeve 71 closely and slidably fittingits upper end. The sleeve 71 is secured in the top plate 43 of theassembly and is provided with suitable fittings, such as nuts 72, forsecuring the whole switch device or assembly to a suitable support. Theplunger 70 is intended to act as a pushbutton for momentary bottomcontact (or while held down) and the plunger for this purpose carries apushbutton finger piece 73 at its upper end.

Preferably when stacks of modules or wafer units are used the plunger 70is made in segments 74, one for each wafer unit in a stack, and thesesegments have reduced ends which telescope together at bars 65, as shownin FIG. 7, to embrace the bars and connect them in the plunger line.

When pushbuttorl actuation is used it is desirable to provide a springreturn for the plunger and bar assembly.

Another is that the contact switch portions can be tempered forspringiness 6 This might be provided for the plunger sleeve (as inFIG. 1) but conveniently may be provided by equipping eacli wafer unitwith a spring 75 under each end of the bar, the springs preferably beingseated at the ends in recesses in the bar and bottom wall of thehousing.

Apertures 76 are provided in the top and bottom walls of the housings(except the bottom wall of the lowest housing where it is not needed)for the passage of the plunger 70. The apertures are shown as beingoversize but may fit closely, if desired, for better guidance and morecomplete dust exclusion. The plunger 70 is retained against excessoutward movement in the sleeve 71 by any suitable means, as here shownby a rubber O-ring or spring ring 77 carried in a groove of the plungerwhich aids also in excluding dust.

The grooved bar 65 provides operation of the switch blades in bothdirections under positive movement and at the same time allowsrelatively free movement with very little friction between the bar andthe switch bladethe flared shape of the grooves allowing the blades toassume various inclined positions without binding. It the blades wereclamped rigidly there would be considerable bending stresses with thepossibility of crystallization and breakage.

The straight bar with grooves can also be readily moved in by endwisetravel from one side of the pre-assembled unit and slid over the ends ofthe switch blades. Then the plunger segments are assembled with the barsand the main plunger and the wafers or modules secured together in thefull assembly. The side plates 49 are removable by endwise movement toopen the housing on the side and permit the bars to be inserted andremoved. The side plates 49 have small projections 49a which engage theinner edges of the stacked spacers 51 to hold the plates in closedposition. There is sufficient spring in the plates to permit them to bemoved in and out.

When it is desired to clean the switch contacts the side plates 49 canbe quickly removed for access. The wafer housing is practically fullysealed against dust but there may be some corrosion over a long periodof time and there may be a slight accumulation of dust. If desired, thebars 65 may also be removed, the plunger elements first being taken out.

The present arrangement is very convenient in the manufacture, sale andeventual use of the switch units. The wafer units or modules 41 can beassembled with all the switch blades and terminal blades clamped inplace between the spacer bars and the whole assembly secured together bythe tubular rivets 45. The side closure members 49 keep out dust andcorrosion in storage. The op erating bars 65 and their springs 75 may beinserted in the original assembly or may be inserted at a later timewhen stacks of wafer units (or one unit if so desired) are set up withthe operating means-pushbutton, relay or the likeand mounted for use.The plunger segment elements 74 are preferably added in final assembly.

The form of water blade anchorage means shown in FIGS. 13 and 14 is muchlike that of the form shown in FIGS. 1 to 4 in that spacer sleeves 11are provided for engagement by the side notches of the switch blades 10'and the terminal blades 32' and that the transverse spacer bars 20 areprovided with holes to fit over the sleeves. At the ends of the spacers20 there are semi-circular vertical spacer elements for the outernotches of the last blades in a row where a full sleeve cannoteconomically be used. Such side spacers 52a are shown in the other formillustrated in FIGS. 10 and 11.

The spacer sleeves 11' and spacer elements may be formed integrally withthe plate 48' or may be made as separate members which are inserted inholes in the plate. When formed integrally, there is preferably anannular depression 11b around the bottom end of the spacers to avoidfillets to interfere with the blade positioning notches.

Rivets 45 secure the parts of the pre-assembled wafer units together;and screws 44' secure wafer units together and to an anchorage part,such as a top plate 43. The bottom spacer 20 is notched into the bottomwall plate 47.

When the spacer sleeve is carried by an upper plate 48 the parts areturned upside down so the blades and 32' and the spacers 20 can bedropped down on the vertical spacer elements 11' and the coordinatingside projections (like 52a of the other form) during assembly.

It is thus seen that the invention provides improved switch mountingmeans, improved switch operating means, improved switch modules andimproved switch housing means.

While certain embodiments of the invention have been illustrated anddescribed by way of example, it is to be understood that there may bevarious other embodiments and modifications within the general scope ofthe invention.

We claim:

1. A switch comprising a housing,

a plurality of essentially parallel resilient, switch contact supportblades side-by-side within and supported by the housing and extendingthrough the Wall and into the housing in essentially coplanarrelationship at one end of the housing so that they are electricallyinsulated from one another,

a rigid insulator actuator bar within the housing transverse to theblades within the general plane of the blades and having slot meansreceiving the other unsupported ends of the blades and movable out ofthe common plane of the blades to deflect the movable contacts, and

a plurality of fixed contacts opposed to individual contacts on theblades so that movement of the blades by the actuator will cause themovable contacts to move in unison between open and closed position withtheir opposed fixed contacts,

said housing closely enclosing the switch contacts, blades and actuatorbar.

2. The switch of claim 1 in which the actuator bar is generallyperpendicular to the blades and mechanically confined so that the endsof the blades cannot escape from the slot means.

3. The switch of claim 1, in which the slot means of the actuator is acontinuous slot so that the bar may be slid in the direction of the slotto receive the ends of all blades extending toward it from one side,said slot being tapered to diverge outwardly in order to permit flexingof the blades without binding.

4. The switch of claim 2 in which two essentially coplanar groups ofswitch contact support blades extend toward the actuator bar fromopposite sides and are received in slots on opposite sides thereof.

5. The switch of claim 4 in which the housing is generally rectangularin shape and thin in the direction of the movement of the contacts andthe actuator bar relative to its width and length, the thickness beingdetermined by the spacing between contact pairs.

6. The switch of claim 5 in which the fixed contacts are supported onblades generally parallel and opposed to the blades supporting theopposed movable contacts so that the respective blades lie generally inplanes defined by the blades which are parallel and close spaced to oneanother.

7. The switch of claim 6 in which the housing is formed by stackingalternately insulator strips transverse to the blades and the blades ina plane and coupling said stacks together to define the end wallsbetween top and bottom walls so that the individual blades extendthrough the end walls to provide terminals for their respectivelysupported contacts.

8. The switch of claim 7 in which side walls of the housing are formedby strips which slide in place between grooves in the top and bottomwalls in their edges which extend laterally beyond the end walls.

9. The switch of claim 6 in which two sets of fixed contacts aresupported on blades generally parallel and opposed to opposite sides ofthe blades supporting movable switch contacts opposite each of therespective fixed contacts so that the respective blades lie generally inthree generally parallel close spaced planes.

10. The switch of claim 9 in which switch contacts are located closer tothe actuator member than to the supported ends of their supportingblades and in which lateral insulating elements are located between thefixed and the movable contact supporting blades such that the fixedcontact supporting blades are limited in their ability to follow themovable blades as they are moved by the actuator bar away from the fixedbar.

11. The switch of claim 10 in which the lateral insulating elements arepart of a grid also having elements extending between the switch bladesand having its edges received in grooves in the top and bottom walls ofthe housing.

12. The switch of claim 5 in which access to the actuator bar isprovided by an opening in the housing which permits entry and access tothe actuator bar of drive means generally perpendicular to the bar.

13. The switch of claim 12 in which the drive means is a manualpush-button fixed to the housing and having means extending into thehousing and into contact With the actuator bar to move said bar.

14. The switch of claim 12 in which the drive means is electromagneticmeans fixed to the housing and having means extending into the housingand into contact with the actuator bar to move said bar.

15. The switch of claim 12 in which the actuator bar is biased into oneposition to which it will return it released and the drive means movesit to another position against said bias force.

16. The switch of claim 5 in which the bias force is provided by theresilience of the movable switch contact supporting blades.

17. The switch of claim 15 in which the bias force is provided byauxiliary spring means acting against the actuator bar.

18. A switch assembly in accordance with claim 12 in which a pluralityof similar switches having their housings fixed together with top andbottom walls adjacent and actuator members are arranged parallel andaligned with a common drive member and in which rigid connectionsegments extend between and into contact with each of the actuator barsin adjacent switch housings passing through aligned openings in the topand bottom housing walls.

19. The switch assembly of claim 18 in which drive means is affixed tothe switch assembly and provides drive means essentially perpendicularto an actuator bar at the top of the assembly through an opening in itshousing and auxiliary spring means is provided between the actuator barmost remote from the drive means and its housing.

References Cited by the Examiner UNITED STATES PATENTS 645,958 3/1900Keller 200-87 2,080,586 5/1937 Varley 200-166 2,298,068 10/ 1942 PierceZOO-87 2,514,913 7/1950 Tyrner 20016 2,886,668 5/1959 Steward et a1200104 2,965,954 12/1960 Baker 200-104 2,986,621 5/1961 Midgley 2001042,992,304 7/1961 Andrews 200104 3,105,128 9/1963 Deissler 200-104BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner.

1. A SWITCH COMPRISING A HOUSING, A PLURALITY OF ESSENTIALLY PARALLELRESILIENT, SWITCH CONTACT SUPPORT BLADES SIDE-BY-SIDE WITHIN ANDSUPPORTED BY THE HOUSING AND EXTENDING THROUGH THE WALL AND INTO THEHOUSING IN ESSENTIALLY COPLANAR RELATIONSHIP AT ONE END OF THE HOUSINGSO THAT THEY ARE ELECTRICALLY INSULATED FROM ONE ANOTHER, A RIGIDINSULATOR ACTUATOR BAR WITHIN THE HOUSING TRANSVERSE TO THE BLADESWITHIN THE GENERAL PLANE OF THE BLADES AND HAVING SLOT MEANS RECEIVINGTHE OTHER UNSUPPORTED ENDS OF THE BLADES AND MOVABLE OUT OF THE COMMONPLANE OF THE BLADES TO DEFLECT THE MOVABLE CONTACTS, AND A PLURALITY OFFIXED CONTACTS OPPOSED TO INDIVIDUAL CONTACTS ON THE BLADES SO THATMOVEMENT OF THE BLADES BY THE ACTUATOR WILL CAUSE THE MOVABLE CONTACTSTO MOVE IN UNISON BETWEEN OPEN AND CLOSED POSITION WITH THEIR OPPOSEDFIXED CONTACTS, SAID HOUSING CLOSELY ENCLOSING THE SWITCH CONTACTS,BLADES AND ACTUATOR BAR.